Compare Samnitici Milites and Neitos for example. Kopides are basically longswords with -1 attack. Also Thorakitai Hoplitai don't perform nearly as well as they used to (regular Thorakitai are substantially more useful now it seems).
Also, not true that Pedites are the only tier 4 kopis unit. Basilikon Agema also fit that criteria. But they are used to being overlooked. Those poor guys couldn't even get good stamina.
And we like the useful spears. At least I do. They're great.
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